孟巴矿特厚煤层分层开采覆岩导水裂隙带高度测定

Determination on the Height of Slice Mining Overburden Rock Water Flowing Fractured Zone of Extremely Thick Coal Seams in Barapukuria Coal Mine of Bangladesh

针对孟加拉国巴拉普库利亚煤矿地表松散富含水层水体下安全开采问题,采用井下仰孔注水测漏法对Ⅵ煤首分层综采采场导水裂隙带发育高度进行了现场探测,实测覆岩最大导水裂隙带高度为61.46 m;应用FLAC3D数值模拟方法,模拟计算了首分层和二分层开采覆岩最大导水裂隙带高度分别为65 m和88 m;通过与经验公式计算结果进行对比分析,综合确定首分层开采覆岩最大导水裂隙带高度为65 m,裂采比为21.67,并给出了中硬顶板条件下分层综采导水裂隙带发育高度计算公式。

Aiming at the safety mining problem under loose surface aquifer water body in Barapukuria Coal Mine of Bangladesh,injection water leakage in upward slant hole method was put forward to monitor height of water conducted zone in first stope which adopted fully mechanized coal mining technology.Monitoring results indicated that the maximum value of the height was 61.46 m in research area.Meanwhile,a numerical simulation about height of water conducted zone was got by software FLAC3D;the values were 65 m and 88 m separately in the first and the second level.After compared with the results from experience formula,the paper finally determined that the real maximum value of height and crack and mining ratio was 65 m and 21.67,besides the paper got a new formula to calculate the height of fractured zone of mid-hard roof with analysis of data regression.